Makes perfect sense - and I agree there's no need to get hung up about 'factory settings' . . . the spring-loaded plunger needs to be screwed in far enough to give positive changes - and not so far that the cam plate can barely rotate from one indent to the next and everything from the gearchange lever inwards gets stressed. No harm can be done by playing with the screw and locknut - but if you take it right out the oil will come too. (Good chance to check the state of the spring etc if you do take it out though). Strongly recommend having a look at a diagram of the camplate, plunger and selector rods/forks arrangement to see exactly how it all works - tho don't have one to offer I'm afraid. I discovered all these things the hard way a few weeks ago, so it's all very fresh!
However, if the gear-change characteristics have changed for the worse simply as a result of a clutch job, I'd suspect the fine adjustment of the clutch too, I have to say . . . maybe a bit of drag there? Springs a tad too tightened up, push rod not lifting the pressure plate quite far enough, etc? I'd certainly play with those aspects before attacking the plunger, but the good news is it can't be anything too serious. Groily